The new Porsche 996 Twin Turbo is an insanely fast and powerful car right off the lot. But to the surprise of no one (least of all loyal ec readers), even the excess of power available to the 996TT driver is insufficient for the True Enthusiast.
But tuning these beasts is not a simple matter, for Porsche and Bosch have implemented the most sophisticated anti-tampering protection yet in the 996TT's Motronic ME7.8 engine management computer. Well, hack-proof systems were made to be hacked, and the hackers in this case are Todd and his merry band of engineers and technicians at Evolution Motorsports in the desert of Arizona. The pair of screaming yellow 2001 996TTs shown here have been brought to a higher state of tune than Porsche would have let out of the factory...but we're glad these two escaped.
The main difference between the two cars is the transmission choice and level of engine tuning. One car is equipped with the new, slicker-shifting Tiptronic auto-manual box and Evolution's "Level 2" tuning, while the other has a six-speed manual with the latest in Evolution Motorsports' insane power mods...what it calls its "Level 4" tuning package.
Evolution Motorsports (EVO for short) offers four "stages" of power tuning for the TT, sized to fit the user's needs...and wallet. The EVO Level 1 system generates peak output of 472 bhp and 484 lb-ft of torque, and produces 63 more midrange hp and 70 more lb-ft of torque un that critical area. The Level I power upgrade consists of EVO's Motronic computer recalibration and AireTEK "Quickflow" air intake modification.
The EVO Level 2 power system, installed on the Tiptronic car, integrates all the features of Level 1 with the addition of an EVO Sport Exhaust system. Peak output is boosted to 490 bhp and 509 lb-ft of torque. There is a midrange power gain of 82 hp at 5000 rpm and 86 lb-ft at 4500 rpm.
Need even more power? The Level 3 system boasts peak power of 545 bhp and 540 lb-ft of torque. All power figures were generated on a two-wheel-drive DynoJet chassis dynamometer. But, Level 3 was not enough for Jason, the owner of the six-speed 996TT. The car came back to Arizona at the beginning of December 2001, the goal to make even more power than offered by EVO's Level 3 system.
EVO's Level 4 system consists of an AireTEK QuickFlow air intake modification, Porsche GT2 intercoolers, modified KKK K-24 turbochargers, an EVO-tuned "Sport" Motronic computer and billet bypass valves. In addition, on the exhaust side of the engine, an EVO Sport Exhaust with high-flow catalysts and a set of EVO equal-length Sport Headers are installed (the headers were fitted after the photo shoot).
Todd recalled the path to insane power: "We started off by addressing the exhaust manifolds and intercoolers. We knew that more power was going to consist of more airflow, better cooling, better fuel and more aggressive computer tuning."
The AireTEK intake system is used in all of EVO's tuning upgrades. The 996TT "QuickFlow" is a simple but effective way to increase airflow and, thus, power. It uses a high-flow, reusable K&N cotton replacement air filter and a new airbox cover.
The OEM exhaust system is restrictive. When EVO started the 996TT project nearly a year ago, its engineers were curious as to what the inside of the stock exhaust looked like. A few minutes with a plasma cutter exposed two restrictive 400 cells-per-sq.-in. catalysts per side and a network of tubes and chambers, seemingly not offering any exhaust direction internally. Todd remembered the discovery: "After studying the design for a while, all I could come up with is that this system was a well-engineered resonance chamber for sound regulations but not a system to maximize power output."
With this in mind, EVO set out to build a better sound-trap. Evolution's stainless-steel canister uses a very simple straight-through design, which offers high exhaust flow for maximum power gains. The units are TIG welded for superior strength and polished to a mirror finish. They can accept the OEM exhaust tips, or they can be fitted with EVO's "S" twin tips. The simple design results in greater performance while enhancing the unforgettable sound of the flat-six turbo motor.
All EVO 996TT sport exhaust systems are a direct replacement for the OEM unit and utilize the same core components. Evolution starts with European 100 cells-per-sq.-in. spiral-wound stainless-steel, platinum-coated race catalysts. These very expensive, free-flowing units keep emissions levels within OBD-II specs, while reducing exhaust backpressure for more power and torque. All the EVO exhaust components have been extensively tested, its chassis dyno test showed gains of 8 to 24 horses at the wheels.